Salt-sensitive hypertension is known to be associated with dysfunction
of the baroreflex control system in the Dahl salt-sensitive (SS)
rat. However, neither the physiological mechanisms nor the genomic
regions underlying the baroreflex dysfunction seen in this rat model
are definitively known. Here, we have adopted a mathematical modeling
approach to investigate the physiological and genetic origins of
baroreflex dysfunction in the Dahl SS rat. We have developed a
computational model of the overall baroreflex heart rate control
system based on known physiological mechanisms to analyze
telemetry-based blood pressure and heart rate data from two genetic
strains of rat, the SS and consomic SS.13BN, on low- and high-salt
diets. With this approach, physiological parameters are estimated,
unmeasured physiological variables related to the baroreflex control
system are predicted, and differences in these quantities between the
two strains of rat on low- and high-salt diets are detected. Specific
findings include: a significant selective impairment in sympathetic
gain with high-salt diet in SS rats and a protection from this
impairment in SS.13BN rats, elevated sympathetic and parasympathetic
offsets with high-salt diet in both strains, and an elevated
sympathetic tone with high-salt diet in SS but not SS.13BN rats. In
conclusion, we have associated several important physiological
parameters of the baroreflex control system with chromosome 13 and
have begun to identify possible physiological mechanisms underlying
baroreflex impairment and hypertension in the Dahl SS rat that may be
further explored in future experimental and modeling-based
investigation.

Pressure-Time series Data

The four *.txt (text) files below contain continuous blood pressure
recordings for 9 Dahl SS rats and 6 Dahl SS.13BN rats, under high and
low salt conditions. Read the comments at the top of each file for details.

For convenience, the data contained in the original text files are also
available in standard PhysioBank format, suitable for study using the
PhysioBank ATM and
the WFDB Software Package. Each
pair of (binary) *.dat and (text) *.hea files below
comprises a PhysioBank-format record that contains data from a single
rat, extracted from the *.txt files.